Conventionally, in a front body structure of a vehicle for reducing the impact acting on occupants at the time when the vehicle such as an automobile comes into frontal collision, a front sub-frame is supported by bolts to brackets which are fixed to a main frame and in which rear-end opening slits are formed, and the bolts on the rear side slip from the rear-end openings of the slits at the time of frontal collision. Accordingly, the main frame can be crushed without the interruption of the front sub-frame. This structure is disclosed in, for example, Japanese Patent Application Laid-Open (JP-A) No. 11-171046.
Further, in another front body structure of a vehicle for reducing the impact acting on occupants at the time when the vehicle such as an automobile comes into frontal collision, a front cross member extending on a front edge of the vehicle along the transverse direction thereof is divided at a substantially central portion of the front cross member into right and left two cross members, and a compass mechanism for symmetrically restricting the rotational movement of the right and left cross members with the respective substantially central portions thereof being as a rotational center is provided at a connecting portion between the right and left cross members. This structure is disclosed in, for example, JP-A No. 11-198854.
However, in the structure of JP-A No. 11-171046, even when the vehicle comes into offset collision, the right and left bolts on the rear side slip from the rear-end openings of the slits, and the impact is absorbed only by the collided front side member. Therefore, the amount of impact absorption in the case of offset collision is less than that in the case of full-lapped collision (full collision), and satisfactory impact absorption cannot be achieved. Further, in the structure of JP-A No. 11-198854, the satisfactory impact absorption is limited by the problem of strength of the compass mechanism against a large collision load.